Desalination ( IF 7.098 ) Pub Date : 2019-12-27 , DOI: 10.1016/j.desal.2019.114301 Ruijuan Zhou; Xiaoxu Guo; Xiaoman Li; Yongshuai Kang; Min Luo
In this work, we used NaxCoO2 as a model system for the first time to explore the effect of Na+/vacancy ordering on desalination performance. An asymmetrical FDI device was developed where NaxCoO2 as the Faradic electrode material and AC act as the Cl-storage electrode material. For x = 0.50, this configuration yields an ultrahigh desalination capacity (130.2 mg g−1), an excellent charge efficiency (100%), and a superior desalination rate (2.61 mg g−1 min−1) in 1000 mg L−1 NaCl solution at 1.4 V. The experimental results reveal that the desalination capacity depends on the range of reversible adjacent intermediate phases region and the desalination rate is affected by the sodium ions mobility in the interlayer determined by the Na+/vacancy ordering pattern between the CoO2 slabs. The excellent desalination capacity and rate are encouraging.